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Chapter 1
somewhat level land, located between
mountains and hills. The difference
between plains and valleys is that plains do
not have hills ormountains on each side of
them. We have many valleys of different
sizes in our state.
Much of our state is covered by a huge
plateau
. A plateau is land that is higher
than the surrounding area. Our plateau can
be quite level in places or very rugged in
other places. Our plateau has all kinds of
landform features. It looks like amountain
region that had its top cut off by somehuge
blade. Our plateau really never had
mountain peaks like those in the western
United States.
You can findmountains, hills, waterfalls,
deep gorges, and glens located on our
plateau. Gorges are deep, narrow passages
through the land with steep rocky sides.
Glens are narrow valleys with water
running through them.
Waterforms
G
eographers also describe places by
their waterforms. Pennsylvania has
many types of waterforms inside its
borders. There are about 5,000 rivers,
creeks, and streams winding through our
state. They make up about 45,000miles of
waterforms. We have three major
river
systems
into which these waterways flow.
A group of tributaries and smaller rivers
that empty intoa larger river is calleda river
system.
Our state has about 2,300 small ponds
and natural lakes. In the northwest,
Lake
Conneaut
is our largest natural lake. It is
onlyone andone-halfmileswide.However,
we have several larger reservoirs located
around the state. A reservoir is a human-
made lake inwhichwater is stored. The lake
is held back by a dam. Pennsylvania has
many dams that are usedmainly to control
flooding of our rivers.
Plants and Animals
P
laces can also be described by the
types of plants and animals that live
in the region. Pennsylvania has the
right kind of climate and soil to support
many types of plants and animals. If you
were todivideour state into ten equal parts,
six of those parts would be covered by
forests. A forest is a large area of land
Shenango Dam, Mercer County, PA.
